Some little-explored spots in Southeast Asia are best left that way. Simmering rebellions, ethnic clashes, and unresolved border issues in some parts of the region simply do not allow for safe travel.
Caught in Crossfire: Kachin & Rakhine States, Myanmar
Tourists visiting Myanmar should take care that they don't walk into the country's hotspots. The country's troubles include firefights between Myanmar government troops and ethnic rebels in the states of Kachin and northern Shan, and an ongoing Buddhist vs. Muslim ethnic conflict in the state of Rakhine.
Wandering off into unsafe areas can cost you your limbs, or your lives. In April of 2016, two German tourists were injured when they set off a mine while walking through a part of Shan State that has seen intermittent clashes between government and separatist forces.
The British Government advises against casual tourist travel to Rakhine State (setting aside the popular Ngapali Beach tourist stop), Kachin State, and the Kokang region of Shan State.
The U.S. Department of State advises its citizens traveling in Myanmar to "maintain a high level of security awareness... avoid crowded public places, such as large public gatherings, demonstrations, and any areas cordoned off by security forces."
Cultural Backlash: Southern Thailand
The southern Thai provinces of Yala, Narathiwat, and Pattani have been under a state of Martial Law since 2005, owing to a simmering rebellion in these parts that has become particularly violent in the past 15 years.
The southern provinces are historically Muslim, once part of the Patani Sultanate that paid nominal tribute to the Siamese Kings up north. Drastic redrawing of borders and a ham-handed government-led attempt to erase the local culture has fueled an ongoing conflict that has killed up to 6,000 people in Southern Thailand between 2004 and 2014.
Visitors to this part of Thailand should take extra care; car bombs have hit the cities of Hat Yai and Songkhla, both important tourist transport hubs in Thailand. The U.S. Department of State prohibits its own personnel from traveling to these provinces in Thailand's far south, and advises tourists to "defer non-emergency travel to these areas."
Tense Relations: Indonesian Papua and Central Sulawesi
Travelers are advised against casual travel to the provinces of Central Sulawesi, Maluku, Papua and West Papua provinces, where simmering divisions have sometimes boiled over.
Central Sulawesi and Maluku have seen some pretty bad bloodshed between the island's Muslim and Christian communities, while an independence movement in the Papua provinces is a continuing source of tension.
While travel to Papua isn't banned, travelers are required to pay for a surat jalan (travel permit) for entry into Papua and West Papua. Remember to pack passport-sized photos and some change to pay for the permit. Read about travel requirements in Indonesia.
Knock-On Effects: Philippines Moro Regions in Mindanao
Insurgent armies on the Philippines' island of Mindanao have been fighting for independence since the 1960s. The local tendency towards warlordism has not improved the situation - political families supported by the central government have built up personal armies ostensibly to battle the rebels, but have also contributed to the local state of chaos.
The unrest in Mindanao has largely been confined to the autonomous region to the far west of the island, but sadly has created knock-on effects on tourism in Davao City and Cagayan de Oro City, to the north and southeast of Mindanao respectively. Both cities are safe for tourists. Read about travel requirements in the Philippines.
Step Lightly: Minefields in Cambodia and Laos
The Vietnam War and the bloody civil war that followed it has left Cambodia as one of the most heavily-mined countries in the world. The Cambodian Mine Action Center (CMAC) estimates that up to 6 million unexploded mines lie underground; this does not include the unexploded bombs left over from repeated bombings by the United States during its campaign in Indochina.
While the Angkor National Park is completely safe, other areas further off the beaten path may still have some nasty surprises lying beneath; the far-flung temple of Banteay Chhmar, in fact, has only been recently cleared of all its mines. A local guide will be able to inform you if you're safe or if you need to walk softly. Read about travel requirements to Cambodia.